New 1972 gmc c15 Super custom owner.

[PaPaStewySnipes]

Hello guys, just went and picked up a 1972 c15. Well to get started it has a destroked 350 (327) in it and a 350 auto with a 2500 stall from what I was told. 327 crank and camel hump heads, maybe a small cam, hooks headers, msd and a 650 holly sa, and edelbrock performer rpm manifold. In great shape, but feels sluggish power wise, doesnt pull like I thought it would. I will be changing all the fluids and doing a seafoam run through it, and just go ahead and do a rebuild on the carb, looks clean but I know the truck has been sitting for 10+ years amd turned over every once in a while. Power steering runs well. Breaks seem weak however everything else runs fine and Idles well any recommendations on where to start on engine. I havent had a chace to pull it apart, I got it today. Tires are dried out so I drove 50mph the whole 30 miles home. I will be starting on breaks, wheels and tires. Ground up, truck has very little rust and I feel like it was a value for 4k. Hints on breaks will be welcomed, I've never owned another chevy truck besides a 87 and I had a 350 in it. Drop in your 2 cents.